Posted 08:40 -- After the 8:30 bell, December corn is down 5 cents, November soybeans are down 16 1/2 cents and September Chicago wheat is down 4 1/2 cents. Corn and soybeans are lower with Tuesday's five-day forecast showing a broader coverage of rain expected across the central Midwest. Wheat prices are also lower after USDA kept its high crop rating for the spring wheat crop in Monday afternoon's Crop Progress report.